Effect of Local Prostaglandin E2 on Uterine and Fetal Doppler Flow in Pregnancy-Induced Hypertension

Abstract

Objectives: To evaluate the effects of vaginal and intracervical administration of prostaglandin E2 (PGE2) on the uterine, umbilical, and fetal blood flow in hypertensive pregnancies.Methods: Thirty-two women with pregnancy-induced hypertension undergoing cervical ripening for preinduction of labor were randomized to receive either 2.0 mg of PGE2 gel vaginally (n = 12), 0.5 mg of PGE2 gel intracervically (n = 10), or placebo gel vaginally (n = 10). The pulsatility index (PI) and resistance index (RI) in uterine arteries, umbilical artery, and fetal middle cerebral artery were calculated before and 30 and 60 min after administration of PGE2 or placebo.Results: Placebo gel caused no changes in any one flow variable. Because the vaginal and intracervical mode of administration of PGE2 caused similar changes in flow, these groups were combined. PGE2 increased (P < 0.0001) impedance to flow in uterine arteries 30 min (9.7 ± 2.8%, mean ± SE) and 60 min (20.5 ± 4.8%) after application. In contrast, impedance to flow tended to decrease in fetal cerebral arteries 30 min (8.1 ± 4.0%, NS) and 60 min (11.5 ± 3.5%, P < 0.004) later. No changes were seen, following PGE2 use, in umbilical blood flow. No clear-cut relationships could be found between changes in blood flow and uterine contractility, as assessed by external tochography.Conclusion: In hypertensive pregnancies, cervical ripening with PGE2 gel leads to increase in uterine vascular resistance, and to decrease in fetal middle cerebral artery resistance.